Math question--How do you read functions???

[Pen]

We are reading Life of Fred where there are simple functions such as, say:

 

2 ---> 4

3 ---> 9

4 ---> 16

 

where the latter number is the square of the first number.

 

How do you read that (or any function) out loud in words? I think my memory of this from my own school days has slipped into a black hole. But I am sure I am not supposed to say "two arrow four". Thanks.

[Cosmos]

I haven't read Life of Fred, but generally in mathematics a function is given a letter name. The letter "f" is most common (those crazy math people!). In your example, if the function were named "f", you would write

 

f(2) = 4

f(3) = 9

 

and you would say

 

f of 2 is 4

 

or

 

f of 2 equals 4

 

Without a name, it's a little difficult to talk about the function. I guess you could say, "The function applied to 2 gives 4" or something like that.

[Pen]

I haven't read Life of Fred, but generally in mathematics a function is given a letter name. The letter "f" is most common (those crazy math people!). In your example, if the function were named "f", you would write

 

f(2) = 4

f(3) = 9

 

and you would say

 

f of 2 is 4

 

or

 

f of 2 equals 4

 

Without a name, it's a little difficult to talk about the function. I guess you could say, "The function applied to 2 gives 4" or something like that.

 

 

Got it. I'll use your last suggestion in these circumstances. Thank you.

[Dana]

Using the arrows is also notation for a mapping and a relation...which doesn't have to be a function.

 

With the arrows, I'd say "2 goes to 4", "6 goes to 36", etc.